PostgreSQL Server not visible in QAN

PostgreSQL pg_stat_monitor
1

Hi to all. I’m new in PMM2 and I’ve recently installed PMM2 and added the PostgreSQL 11 server. I’ve installed pg_stat_monitor. I’ve done it as it mentioned in this document (PostgreSQL - Percona Monitoring and Management). As a result, this server has appeared in “PostgreSQL Instance Overview” dashboard but has not appeared in QAN (Query Analytics). What else do I need to do to make it appear in QAN?

Capture
Capture764×1045 166 KB

1 Like
2

Hi Nikode,

It can be possible that you have metrics and not queries, since the exporters are different. The first thing I would check here is if pg_stat_monitor is indeed working as expected:

postgres=# select count(*) from pg_stat_monitor;

And check the PostgreSQL log file, too. If it is, you can then check the PMM client-side logs:

sudo journalctl -u pmm-agent | tail

If it’s working correctly, you should see no error messages and also see messages about buckets being sent.
You can also get the PMM server logs and inspect the different processes running within the server itself. Click on the cogwheel at the bottom left and you should get the download button to get a zip file with all logs.
Finally, make sure that you are selecting a time range in which you were effectively gathering data.
Let me know what you are able to find out with this, or if you need more guidance on it.

2 Likes
3

Hello Agustin_G,
First of all thanks for reply.

I am sending you pictures according to your questions:

  1. This is select result
    Capture

  2. This is sudo journalctl -u pmm-agent | tail result

    Capture2
    Capture21659×298 157 KB

  3. This is postgresql log file, I don’t use pg_stat_statements

    Capture3
    Capture31967×242 62.7 KB

  4. This is qan-api2.log

    Capture4
    Capture41405×439 77 KB

If you are interested in anything else, I can write to you.
Thanks in advance.

1 Like
4

Niko,
Ok, so the pg_stat_monitor extension is working ok. How did you add the instance? Note that you should explicitly use:

shell> pmm-admin add postgresql --help
...
      --query-source="pgstatements"                  Source of SQL queries, one of: pgstatements, pgstatmonitor, none (default: pgstatements)

So, the command should be like:

shell> pmm-admin add postgresql --query-source=pgstatmonitor [OTHER_OPTIONS]

Since you can’t update an already-running pmm-client, you will need to remove and re-add:

shell> pmm-admin remove postgresql <service_name>

and then use pmm-admin add as shown above.

Let me know if this works.

Best,
Agustín.

1 Like
5

Hello Agustin,

I’ve deleted and added service again, with option --query-source=pgstatmonitor

pic001
pic0011843×105 34.8 KB

then I’ve run some selects

pic002
pic0021501×303 54.5 KB

but in QAN not shown POSTGRESQL_LCM_PRE service again :frowning:

pic003
pic003557×831 70.6 KB

Thanks in advance.
Best,
Niko

1 Like
6

Agustin,
Finally, the service appeared in QAN :slight_smile: , It seems that the service took some time to display on the dashboard :slight_smile:.
Thank you for valuable advice. It seems that the solution was --query-source=pgstatmonitor
Thank a lot and HAPPY NEW YEAR! :wink:
Best,
NIKO

1 Like
7

Glad to hear it worked! Thanks for the update.

Happy new year to you too! :slight_smile:

1 Like